Chair having a jointless seat



K. VESTERHOLT ETAL 3,069,204 CHAIR HAVING A JOINTLESS SEAT Dec. 18, 19622 Sheets-Sheet 1 Filed Feb. 13, 1961 A i. k

INVENTOR S wwwm o O m n n w V LU mw um n ee fi/QJ Irv Jav- BY Dec. 18,1962 l. K. VESTERHOLT ETAL 3,

CHAIR HAVING A JOINTLESS SEAT 2 Sheets-Sheet 2 Filed Feb. 13, 1961INVENTOR Z379 )frabe Ves'fIr/zol?" ATTORNEYS United States Patent fifice3,069,204 Pat ented Dec. 18, 1962 The invention relates to a method forthe manufacture of a seat for a piece of furniture for sitting with aback rest connected thereto, from a plate blank, and a chair with a seatmanufactured by this method.

One object of the invention is to provide a convenient seat for a pieceof furniture for sitting, particularly a chair, from plate material by asimple and cheap method.

Another object of .the invention is to provide a chair with such a seat.

A further object of the invention is to provide a seat for a piece offurniture for sitting to which seat supports are easily fixed.

A further object of this invention is to provide a seat having aconvenient sitting line.

Still a further object of this invention is to provide a strong seat fora pieceof furniture for sitting, which seat is made from a thin plateblank by a simple bending and folding operation.

Other objects of this invention will appear hereinafter.

The objects of this invention may be accomplished, in general, byperforming one, two or more foldings of the plate blank for obtainingthe shape desired, each folding comprising a bending of the plate blankalong at least two intersecting lines, from the perimeter to the pointof intersection of said lines so that the bendings are consecutivelyperformed in opposite directions.

By this method a seat of a convenient form is obtained in a simple way.

The seat according to the invention is preferably produced by the plateblank being given two folds located symmetrically with respect to anaxis of symmetry for the blank.

The invention furthermore relates to a chair with a seat manufactured bythe method according to the invention, and the characteristic feature ofthis chair is that the supports are of tube material or bar material,the central section of which is bent substantially into U-shape in aplane substantially at right angles to the leg portion or portions ofthe tube or the bar, while said leg portion or portions of the tube orthe bar are accommodated in the fold or the folds and screwed on to theseat along one folding line.

The .invention will be more easily understood by reference to thefollowing detailed description when. taken in connection with theaccompanying illustration, in which FIG. 1 shows a circular plate blankwith indicated bending lines for the manufacture of a seat according tothe invention.

FIG. 2 shows a part of another circular plate blank I In the drawing, 1indicates a plate blank for the manufacture of the seat according to theinvention. The plate blank is in the drawing shown circular, but mayalso have other shapes. ample at opposite sides of a line of symmetry 2be straight lines of a certain length. More intricate shapes of theperiphery of the plate blank may also be taken into consideration.

In FIG. 1 3-6 indicate bending lines. The lines 3' and 4 are symmetricalwith the lines 5 and 6 with regard to the line of symmetry 2. The platematerial is bent along the bending lines into forming folds in the platematerial due to which folds the plate material gets the shape desired.

furthermore bent slightly along a line 9 the plate material will assumethe shape shown in FIGS. 3 and 4. The dotted arrow 7 in FIG. 1 indicatesthatthe lines 3 and 5 after the bending will lie below the platematerial when the latter is still viewed from the same side as in FIG.1, f while the fully drawn arrow 8 indicates that the lines 4 and 6after the bending Will lie above the plate material,

when the latter is viewed in the same manner as above When the platematerial is bent in this simple way,

a particularly convenient seat is obtained. Not only ient sitting line10. In spite of the fact that the bendings performed by the methodaccording to the invention are performed solely as single-curvedbendings of the plate.- material, they give the seat as well as the backrest a This double-curved surface contributes in part to increasing thestrength of the seat, so

double-curved surface.

that the thickness of material of the plate blank may be comparativelysmall, in part contributes to making the seat more comfortable to sitin.

The attainment of the double-curved surface is due solely to thestresses in the material produced by the bending and to an elasticdeformation produced by these This deformation may incidentally give thef stresses. seat better elastic properties than such a continuous defingto the invention.

It has been described above that the plate material is given two foldsby bending along the lines 3-6, where the lines 3 and 4 and the lines 5and 6 are symmetrical with regard to the line of symmetry 2. Also otherembodiments of the invention may be taken into consideration;

the plate material may e.g. be given a single fold as exemplified inFIG. 6, or more than two folds. This latter f case also includes doubleor multiple folds at the same place as exemplified in FIG. 2. In thisfigure 3a and 4a 1 are bending lines. The bending lines 3a will, asindicated by the dotted arrow, after the bending be situated below theoriginal surface of the plate blank, while the bending lines 4a, asindicated by the full line arrows 8n will be situated above the originalsurface of the plate 9 blank, when the plate blank is seen as shown inFIG. 2. J.

In an expedient way of carrying out the method according to theinvention, each of the folds is produced by bending around two lines insuch a way that the line,

which before the bending lies nearest the part of the blankcorresponding to the back rest, will be outermost after the bending.Hereby is attained that the back rest gets an expedient curvature.

In another expedient way of carrying out the, method .1:

Part of the periphery may for ex-' If the plate blank in FIG. 1 is bentas shown by bending along the lines 36, so that the bending takes placeas indicated by arrows 7 and 8 and is l;- according to the invention thefold or the folds are made in such a way that the said fold or folds canbe used for accommodating the supports for the seat. When produced froma tube or a bar with a round cross section, the supports will in thisway get a particularly good rest against the seat along the curvedsurface of the fold, which curved surface may follow the curved surfaceof the support over a considerable area. Hereby the chair becomesparticularly stable.

With reference to FIGURES 3 and 4 showing a chair with a seat producedby the method according to the invention, 11 is the said seat. By theproduction of each of the folds by bending around the two lines 3, 4 and5, 6 two triangular tongues 12 and 13 are produced. The bending isperformed in the way that the line, which before the bending liesnearest the part of the blank corre- Spending to the back rest, will belocated outermost after the bending. In this way the two tongues 12 and13 will be produced in such a way that the tongue 12 will lie outermost.It will be seen that the outer tongue in this way, together with a part15 of the plate material, which is bent slightly upwards, will form asuitable arm rest. The tongues 12 and 13 are preferably not bent so muchthat they are pressed together, but so that suitable openings 16 and 17are formed between them. In the opening 16, the innermost plate of whichis curved, the supports 18 are inserted and can be secured here e.g. bymeans of screws or by gluing or welding, e.g. spot welding. The supportsshown are made of a rod member which may be tubular and which is bentapproximately 90 at 19, 20, 21, and 22, so that the plane determined bythe lines 19, 22, and 20, 21 is substantially at right angles to thevertical parts 18 of the support. The free ends of the latter are led inbetween the tongues 12 and 13 and secured by means of screws 23. Thissupport of the seat is very convenient, as it gives a stable and strongconnection between support and seat.

In FIG. is shown a modification of the chair shown in FIGS. 3 and 4. Inthis modification the free ends of the support 18 are extended past theopening 16 and at 23, 24, 25, 26, 27, and 28 bend at substantially rightangles to form partly arm rests 28 and 29 and partly a support 30 forthe front part of the seat, said support 30 extending beneath the seatin the vicinity of the line 9.

FIG. 6 shows another embodiment of the chair according to the invention.The seat 31 of this chair is produced by providing a plate blank, e.g.as shown in FIG. 1, with a single fold 32 according to the invention. Byproviding this fold the plate blank, apart from secondary bendings, e.g.along the line 33, is given the desired shape. In the fold a support 34is secured e.g. by means of screws 35, said support e.g. having the formof a substantially vertically extending portion 36 extending into andsecured in the fold as described and a substantially triangular orcircular portion, the plane of which is substantially at a right angleto the portion 36.

FIG. 7 shows the chair of FIG. 3 the seat of said chair being providedwith upholstery, e.g. as shown in the figure a substantially circularcushion 38, which is placed in the seat 11 and at the foldings presseddown into the corners 17 of the foldings. FIG. 8 shows a cutaway of thecushion and 39 designates a plate of foam plastics while 40 designates acover of a plastic or fabric material.

The upholstery may also be a plate of foam plastics, e.g. a foam rubberplate, which is e.g. glued to the plate material of the seat.

The plate material may be metallic, e.g. of iron or aluminium, but mayalso be plastic material, including glass-reinforced plastic. Furtherthe plate material may be perforated.

We have described preferred embodiments of our invention, but it isunderstood that this disclosure is for the purpose of illustration andthat various changes in shape, proportion and arrangement of parts aswell as the substitution of equivalent elements for those herein shown dand described may be made without departing from the spirit and scope ofthe invention as set forth in the appended claims.

We claim:

1. A chair having a jointless seat with a back rest integral with saidseat, which seat is made from a substantially plane plate blank with anunbroken outer periphery and an uninterrupted surface area within saidperiphery comprising one fold comprising bendings in said plate blankalong a plurality of intersecting lines from the perimeter to the pointof intersection of said lines in consecutively opposite directions,which chair further has a support of a rod member, the central part ofsaid rod member being bent into a figure lying substantially in a plane,said plane being at substantially right angles to the substantiallyvertical part of the support while the vertical part of the support isaccommodated in the corresponding fold and screwed on to the seat alongone folding line.

2. A chair having a jointless seat with a back rest integral with saidseat, which seat is made from a substantially plane plate blank with anunbroken outer periphery and an uninterrupted surface area within saidperiphery comprising one fold comprising bendings in said plate blankalong two intersecting lines from the perimeter to the point ofintersection of said lines in opposite directions, which chair furtherhas a support of a rod member, the central part of said rod member beingbent into a figure lying substantially in a plane, said plane being atsubstantially right angles to the substantially vertical part of thesupport while the vertical part of the support is accommodated in thecorresponding fold and screwed on to the seat along one folding line.

3. A chair having a jointless seat with a back rest integral with saidseat, which seat is made from a substantially plane plate blank with anunbroken outer periphery and an uninterrupted surface area within saidperiphery comprising two folds each comprising bendings in said plateblank along a plurality of intersecting lines from the perimeter to thepoint of intersection of said lines in consecutively oppositedirections, which chair further has a support of a rod member, thecentral part of said rod member being bent into a figure lyingsubstantially in a plane, said plane being at substantially right anglesto the substantially vertical part of the support while the verticalpart of the support is accommodated in the corresponding fold andscrewed on to the seat along one folding line.

4. A chair having a jointless seat with a back rest integral with saidseat, which seat is made from a substantially plane plate blank with anunbroken outer periphery and an uninterrupted surface area within saidperiphery comprising two folds each comprising bends in said plate blankalong two intersecting lines from the perimeter to the point ofintersection of said lines in opposite directions, which chair furtherhas a support of a rod member, the central part of said rod member beingbent into a figure lying substantially in a plane, said plane being atsubstantially right angles to the substantially vertical part of thesupport while the vertical part of the support is accommodated in thecorresponding fold and screwed on to the seat along one folding line.

5. A chair having a jointless seat with a back rest integral with saidseat, which seat is made from a substantially plane plate blank with anunbroken outer periphery and an uninterrupted surface area within saidperiphery comprising two folds disposed symmetrically with respect tothe line of symmetry for said seat, each of these foldings comprisingbendings in said plate blank along two intersecting lines from theperimeter to the point of intersection of said lines in oppositedirections, where the outer tongue of each fold extends from the backrest portion of the seat, which chair further has a support of a rodmember, the central part of said rod member being bent into a figurelying. substantially in a plane, said plane being at substantially rightangles to the substantially vertical part of the support while thevertical part of the support is accommodated in the corresponding foldand screwed on to the seat along one folding line.

6. In a chair according to claim 5 the supports extending through thefolds and being bent at substantially 90 in a direction away from theback rest adjacent the folds.

7. In a chair according to claim 5 the supports extending through thefolds and being bent at substantially 90 in a direction away from theback rest adjacent the fold, and further being bent at substantially 90in a downward direction and further at substantially 90 underneath theseat.

8. A chair having a jointless seat with a back rest integral with saidseat, which seat is made from a substantially plane plate blank with anunbroken outer periphery and an uninterrupted surface area Within saidperiphery comprising a folding comprising bends in said plate blankalong a plurality of intersecting lines from the perimeter to the pointof inter-section of said line-s in consecutively opposite directions,which chair further has a support of a rod member, the central part ofsaid support rod member being bent into a figure lying substantially ina plane being at substantially right angles to the substantiallyvertical part of the support while the vertical part of said support isaccommodated in the corresponding fold and screwed on to the seat alongone folding line, said seat being provided with upholstery.

References Cited in the file of this patent UNITED STATES PATENTS

